1875.] 



SENATE— No. 75. 



13 



I myself arranged the collection of European Lepidoptera, 

 tliose of the United States, of the Himalaya and the general 

 collection of the Ehopalocera, filling 26 cabinets. By the 

 new arrangement of the exhibition rooms the insect cabinets, 

 formerly scattered in all of the rooms, are transferred to a 

 separate room. 



The Xeuroptera sent by the diflferent United States expedi- 

 tions mentioned before, are determined, and the reports de- 

 livered to the parties, to be published. Unfortunately the 

 insects were nearly all in a condition unfit for a scientific 

 collection. 



The second part of the Lepidoptera from Texas in the col- 

 lection, was published by Prof. Zeller. A large part of the 

 Xoctuidse of the United States are identified and named by A. 

 E. Grote, from Bufialo, N. Y., and the California Phaleenidae 

 by Mr. A. S. Packard. 



Several lots of duplicates of Lepidoptera were sent in 

 exchange for North American species that were wanting in 

 the collection. 



Perhaps an interesting and important fact may be men- 

 tioned here. The alcoholic vials of the biological collection 

 were a year ago all newly arranged with rubber stoppers, the 

 cork stoppers not doing well here owing to the great chansfes 

 of temperature. The whole collection is now perfectly safe. 

 The corking of the vials was made in a peculiar way, sug- 

 gested by Mr. D. F. Becker. In putting the stopper in the 

 vial a fine insect-pin is introduced (to be removed later), 

 allowing the air to escape, and preventing at the same time a 

 strong compression of the alcohol. Formerly the compres- 

 sion of the alcohol was a principal cause for the want of safety 

 of the filled vials. 



A small test-vial, filled in this way a year ago, was kept 

 purposely the whole year in the sunshine ; the length of an 

 air-bubble retained in the vial was measured carefully in 

 millimetres, and shows now about the same length as a year 

 ago. In summer the bubble was even much smaller, owing 

 to the greater expansion of the alcohol, proving at the same 

 time the close fitting of the stopper. 



